In the chemical reaction \(N_2 + 3H_2\rightleftharpoons2NH_3\) at equilibrium point, state whether:
(a) Equal volumes of N2 and H2 are reacting
(b) Equal masses of N, and H2 are reacting
(c) The reaction has stopped
(d) The same amount of ammonia is formed as is decomposed into N2 and H2